Infiniti G20 Nissan Primera Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
973 Posts
Discussion Starter #1
I got a fuel pressure gauge hooked up between the fuel filter and the fuel rail.

Pressure reads 38 psi and 45 psi with the vacuum hose disconnected.

(I know its supposed to be 36/43 but I think this should be close enough in terms of a normal starting car for sure).

I was wondering if the pressure is supposed to remain the same indefinitely or will it drop slowly over night?

Should I just be checking fuel pressure at startup?

Based on my present findings, I don't think fuel pressure is the problem as far as my cold start issue is concerned.

Just what am I supposed to be checking for? I won't really be able to see the gauge while its cranking.

Thanks
 

·
Registered
Joined
·
973 Posts
Discussion Starter #2
so I came back this morning and there was like 5 psi in the fuel system...is that normal? doesn't all the fuel go back to the tank???
 

·
Registered
Joined
·
973 Posts
Discussion Starter #3
bumpity bump...

I have been doing some reading, and this is not a normal function.....

The check valve is supposed to keep pressure up overnight in the fuel pump.

Or the injectors are leaking.

Please help me troubleshoot.

Could my remanned injectors be bad?
 

·
Registered
Joined
·
973 Posts
Discussion Starter #5
When it primes it comes back to normal right away. Everything that I have read says that the priming is not enough. That the short burst of fuel provided by the prime is just a short burst of fuel, and that there will be air trapped in the lines as a result of the drop overnight.

Please take a look at this (the 92 integra part) :

http://autotechrepair.suite101.com/article.cfm/an_acura_integra___a_mazda_626

and this (a little log winded):

http://groups.google.com/group/alt....e+gauge+morning&rnum=2&hl=en#2929d21ac96f547a

I read that I could clamp off the return and inlet lines then see if the pressure goes down thereby isolating the injectors, but now sure how to do that quickly and effectively without getting fuel all over the place.



What do you all think?
 

·
Registered
Joined
·
973 Posts
Discussion Starter #6
Mechanic says that it is normal for the pressure to drop to 0 in the morning.
 

·
Registered
Joined
·
1,361 Posts
jj94auto said:
Mechanic says that it is normal for the pressure to drop to 0 in the morning.
Your mechanic is absolutely correct. Fuel pressure will drop over time. That is normal. When you turn your key to the start position the fuel pump will re-pressurize the system.
 

·
Registered
Joined
·
973 Posts
Discussion Starter #8
Thank God, and thank you! :)
 

·
Registered
Joined
·
973 Posts
Discussion Starter #10
Thanks, but is the pressure supposed to drop right before my eyes?

The fuel pressure is down to 20 psi within 5 minutes and down to 5 psi within no time at all.
 

·
Registered
Joined
·
973 Posts
Discussion Starter #12
cool, thanks
 
1 - 12 of 12 Posts
Top